Make VR screen tap tests more stable

chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/OnDispatchTouchEventCallback.java

Index: chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/OnDispatchTouchEventCallback.java
diff --git a/chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/OnDispatchTouchEventCallback.java b/chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/OnDispatchTouchEventCallback.java
new file mode 100644
index 0000000000000000000000000000000000000000..c45a2acebafb832f63ab4743aef38698e18644b4
--- /dev/null
+++ b/chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/OnDispatchTouchEventCallback.java
@@ -0,0 +1,17 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.vr_shell;
+
+/**
+ * Callback used to execute code additional test code after VrShellImpl's
+ * dispatchTouchEvent() runs.
+ */
+public interface OnDispatchTouchEventCallback {
+    /**
+     * Runs some code that may need to know if the event was consumed
+     * by the parent and if a cardboard event was triggered.
+     */
+    void onDispatchTouchEvent(boolean parentConsumed, boolean cardboardTriggered);
+}